Carriage for cutting or sawing machines



w. w. GARDNER TAL 2,297,882

CARRIAGE FOR CUTTING OR SAWING MACHINES Oct. l6, 1942.

Filed April 4, y1940 Patented Oct. 6, 1942 UNITED STATES PATENT OFFICE CARRIAGE FOR CUTTING OR SAWING MACHINES Pennsylvania Application April 4, 1940, Serial No. 327,812

4 Glaims.

This invention relates to improvements in carriage construction for cutting or sawing machines and more particularly to improvements in safety devices associated with such carriages,

In the operation and use of sawing and cutting machines having cutting elements rotating at high speed and being movable relative to a supporting member, some danger is experienced in that the cutting element may be moved adventitiously to the peril of an operator.

An object of the present invention is to provide safety mechanisms in conjunction with a movable high speed cutting elem-ent, which safety mechanisms are automatically operable, when an operator releases the cutting element, to hold the same against movement relative to its support.

Another object of the invention is to provide a releasable locking device associated with a movable high speed cutting element, which locking device can be readily operated to permit movement of the cutting device at an operators will.

A further object of the invention is to provide a trigger mechanism associated with the handle of a movable high speed cutting element, which i trigger can be moved to release the cutting element for movement when the handle is gripped by an operator, and which trigger automatically moves to relock the cutting element against movement when the handle is released.

In carrying out the foregoing and other objects of the invention, use is made of a locking member associated with a carrier for a high speed cutting element. This carrier is preferably provided with a handle for manipulation by an operator and the carrier is mounted for movement relative to a suitable support. The carrier, in conventional fashion, may be mounted either in an arm extending from a support for movement relative to the arm or may be secured at the end of an arm, which arm is movable relative to the support. v

The present invention provides means whereby movement of the cutter carrier relative to the support is prevented when an operator has released the handle. To this end the invention in its preferred form makes use of a rack member secured Within an arm having tracks for the support of a carriage on rollers. The carriage itself is provided with a cooperating member having teeth to engage the teeth of the rack, such member being normally spring pressed into engagement with the rack to prevent movement of the carriage. The carriage is provided with a handle to which is secured a trigger member connected by suitable linkage to the cooperating member so that when the handle is gripped by an operator, the trigger serves to operate the linkage to dis-engage the locking member from the rack whereby the carriage can be moved relative to the arm. When the handle is released by an operator the spring means associated with the locking member restores such locking member to engagement with the rack so that accidental movement of the carriage relative to th'e arm is prevented.

Other features, objects and advantages of the invention will become apparentI by reference to the following detailed description, wherein Fig. 1 is a view partially in vertical section of such parts of a sawing or cutting mechanism as are necessary to illustrate the invention, such view showing the locking mechanism partially in section and partially in side elevation;

Fig, 2 is a section taken substantially on the line 2 2 of Fig. 1, and

Fig. 3 is an enlarged top view of the locking element associated with a rack secured in the arm.

Referring now to the drawing wher-ein parts of one conventional type of structure for the manipulation of a high speed cutter are illustrated, Il) represents generally a portion of a horizontally extending arm, which arm can be elevated and moved about a vertical axis in the usual fashion. This arm has as a part thereof two oppositely disposed tracks II extending in an angular direction, and two oppositely disposed tracks I2 aligned in a horizontal plane.

Also secured within the arm and extending lengthwise thereof is a rack member I4 having a Dlurality of teeth I5 in the underside thereof.

Associated with the arm is a saw carriage indicated generally at I6 which carriage has two pairs of rollers I'I adapted to roll on the tracks I I and two pairs of rollers I8 adapted to be forced against and roll on the upper tracks I2. The carriage itself may be of any desired shape permitting the mounting thereon of the respective pairs of rollers. Secured to the carriage by means of a king pin I9 is a yoke member 2D which serves as a hanger for an electric motor 2| having a cutting element 22 either directly secured to the motor shaft or geared thereto. As shown in Figs. 1 and 2., the king pin I9 has its upper portion of larger diameter than the lower portion 4which passes through an opening in the carriage I6 and also through an aligned opening in the yoke 20. The lower end of the king pin I9 is externally threaded 55 for the reception of a nut 24 having a handle 25 f extending therefrom which is used to fasten the yoke against rotation relative to the carriage. The yoke 2G is provided with a handle 2B which can be gripped by an operator to move the yoke and carriage as a unit relative to the arm l0.

The king pin I3 is provided with a bore 21 and with a counterbore 28. Extending through the king pin is a plunger member 3B having a part fitting within the bore 21 and a part fitting within counterbore 28. Also located in the bore 21 and surrounding plunger 3!) is a coiled spring 3l which serves to force the plunger 30 upwardly.

Secured to the top of the plunger 30 is a locking element 32 which is fastened to the plunger by means of a hollow headed screw 34 passing through the bottom of a recess in the member' 32 into a threaded aperture in the top of the plunger. A washer 35 surrounds the shank of the set screw 34 and permits this screw to be tightened sufficiently to lock the same in place while at the same time the member 32 has a portion seated on a step on the top of the plunger 3i? so that the member 32 is free for rotation relative to the plunger. The lower end of the plunger 30 extends below the lower end of the king pin I9 and is provided with a through transverse slot 31, the floor of which is slightly rounded as shown at 33. A lever 39 is pivotally secured to the yoke 2K) and has one end thereof extending through the slot S1. beyond the yoke to a point adjacent the top of the handle 26. A trigger member 46 is pivotally secured in a suitable slot in the handle and the trigger has one end part thereof cammed as at 4| to bear against the under surface of the outer end of lever 39.

The locking member 32 is of general rectangular shape and as before mentioned has a centrally disposed recess 45, the bottom of which is apertured for the passage of the shank of .the screw 34; the head of such screw being seated inthe recess 55. Member 32 has two upstanding walls 46 spaced apart sufficiently to permit them to engage the opposite side edges of the rack I4. The floor of the locking member between the side walls 48 is provided with a plurality of teeth 41 shaped and disposed to engage the teeth l5 of rack i4. The side walls S5 serve to prevent rotation of the locking member 32 relative to the rack i4 but at the same time do not interfere f with rotation of the king pin and plunger 30 relative to the locking member. These side walls extend upwardly suiciently to assure proper engagement of the locking member with the rack for the prevention of rotation of the locking member in even its most depressed position wherein the teeth of the cooperating parts are out of engagement.

The operation and use of this safety mechanism is substantially as follows. The normal 'positions of the various parts are shown in Fig. 1 wherein it will be seen that the locking member 32 is pressed upwardly by spring 3l to cause engagement of teeth 41 of this locking member with teeth l5 of the rack. In this position the carriage is effectively locked against movement along the tracks l I and i2 of the arm H). Likewise, as shown in Fig. 1, the trigger 40 extends outwardly relative to the vertical expanse of handle 2t, also under the impetus of the spring 3l.

When an operator desires to move the carriage longitudinally of arm itl, gripping of handle 26 by the operator causes pivotal movement of trigger iii which in turn rocks the lever 39 about its fulcrum, pulling the plunger 3G downwardly The other end of the lever 39 extends Y to thereby disengage teeth 41 from teeth I5. When such disengagement has been accomplished, the carriage and yoke with motor and saw attached can be moved as a unit with the pairs of rollers rolling on their respective tracks. When the operator releases the handle the spring 3l restores the parts to the Fig. 1 position locking the carriage against any longitudinal movement relative to the arm. The yoke may be in any angular position relative to the carriage without interfering with the operation of the safety mechanism, since the king pin and plunger can rotate relative to the locking member.

From the foregoing it will be seen that the present invention provides safety mechanism for preventing accidental movement of a saw or other cutter carrier relative to its support so that the chances of the cutter endangering an operator are materially lessened. This device is of particular importance in installations wherein the support for the carrier may be mounted on an unstable surface such as, for example, on board ship, in which instances the normal movement of a ship might cause movement of the carriage to the danger of an operator if such carriage were not locked against movement when not in actual use or under the direct control of the operator. It is to be understood that the illustrated embodiment shows merely one form of the invention and that any limitations imposed upon the same are to be only those set forth in the following claims.

i/Vhat is claimed is:

l. In apparatus 0f the character described, a horizontally extending arm, a support, a carrier for a rotatable cutter, said carrier being secured to said support for movement longitudinally thereof, a motor yoke pivotally secured to said carrier, said yoke being provided with a handle for causing movement of the yoke and carrier as a unit, a rack secured to said arm, a rotatable plunger extendin'I axially through said yoke and through said carrier, a toothed locking member on one end of said plunger, means for yieldingly forcing said toothed member into engagement with said rack to normally look said carrier against movement relative to said support, and releasing means rotatable with said yoke, said releasing means being connected to said plunger and adapted to be actuated when said handle is gripped to release said toothed member from said rack whereby said carrier can be moved, said toothed member being held against rotation relative tov said rack.

2. In apparatus of the character described, a horizontally extending arm, a carrier secured to said arm for movement longitudinally thereof, a yoke secured to said carrier for rotation relative thereto about a vertical axis, a motor driven rotatable cutting element mounted in said yoke, cooperating members carried by said arm and said carrier for normally locking said carrier against longitudinal movement relative to the arm, and releasing means carried by said yoke and connected to one of the cooperating members, said releasing means being rctatabie along with said yoke while said cooperating member to which the releasing means is connected is held against rotation.

3. In apparatus of the character described, a horizontally extending a carrier secured to said arm for movement longitudinally thereof, a yoke secured to said carrier for rotation relative thereto about a vertical axis, a motor driven rotatable cutting element mounted in said yoke, co-

operating members carried by said arm and said carrier for normally locking said carrier against longitudinal movement relative to the arm, means for holding said cooperating members against relative rotation, and releasing means carried by said yoke and connected to one of said cooperating means, said releasing means being rotatable along with said yoke while said cooperating members are held against rotation.

4. In apparatus of the character described, a horizontally extending arm, a rack secured to said arm, a carrier secured to said arm for movement longitudinally thereof, a yoke secured to said carrier for rotation relative thereto about a vertical axis, a motor driven rotatable cutting element mounted in said yoke, a toothed member normally biased to engage said rack and held against rotation relative to the rack, a plunger for moving said toothed member, and releasing means carried by said yoke and connected to said plunger, said releasing means and said plunger being rotatable along with said yoke while said 10 toothed member is held against rotation.

WALLACE W. GARDNER. EWALD SCHUTZ. 

